Incorrect lamp pyramid diagram 7-13-2

Table 1-8.—Sample Video Processing and Distribution System Checkout Procedures In our sample troubleshooting problem, the faulty component is Test Board 25A38A31. To isolate this component, the technician performs the checkout procedures shown in table 1-8. At step 27, the tech- nician observes that none of the lamps on 25A38 are lit. From here, the technician proceeds to the problem directory (see table 1-9), step 27, where he is directed to set the S/P BYPASS switch to ON. After doing this, he notices that more than one lamp is out on 25A38. The problem directory refers the technician to the incorrect lamp indicator pyramid diagram, shown in figure 1-8. Figure 1-8.—Incorrect lamp pyramid diagram 7-13-2. Here, the technician follows the instructions out- lined in the dashed blocks and answers the questions in the solid block. Eventually, the technician is in- structed to measure the voltage at 25A38A3lTPI. A zero-voltage reading at this test point indicates that Test Board 25A38A31 is the faulty component. The technician replaces the circuit board and verifies correct operation by repeating step 27 in the checkout procedures. Figure 1-9 is a sample troubleshooting system fictional diagram. 1-22